I decide to go into file explorer and delete anything that I don't need. I finish with a few folders that have weird names (but none in any special android system folder as far as I know) that I thought might be remains of spam apps I downloaded a while back; and since then my phone refuses to charge wirelessly !

meaning it charges through USB. It also charges when placed on the wireless charging pad, it lights up recognizing the phone but the phone does nothing, yet if I switch the phone off (essentially killing the software) it'll charge wirelessly without a problem ...

What have I messed up, and how can I fix this ?

PS: I restored from an old backup and the wireless works flawlessly too. So it is just this "current state" of the phone which is messing up.
Also I'm guessing it's a folder I deleted, because my wife's phone has the exact same issue (decided to clear hers at the same time as mine before realizing I had messed up).

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